The invention relates to a fuel injection pump for internal combustion engines having a piston which is adjustable counter to a restoring force by a fluid from a supply pump. The generated restoring force is in proportion to engine rpm for adjusting injection onset and having rpm-proportional control of the fluid pressure via a pressure control valve. A displaceable control piston is provided between a pressure chamber and a restoring chamber counter to a restoring force and arranged to determine a spill cross section. A throttle connection is also provided between the pressure chamber and the restoring chamber. A discharge control device is connected to the restoring chamber which also includes a valve that functions in accordance with engine characteristics.
In a known fuel injection pump of this kind, a pressure valve is disposed in the outflow channel, the valve being controllable via a thermostatic valve. The opening of this valve is effected in accordance with temperature. The variation of the normal adjustment characteristic of the injection adjuster effected by this supplementary control accordingly acts over the entire rpm range, which is associated with an impairment of the exhaust gas quality as well as of the efficiency of the engine.